In general, in a building, a window (an opening) is a place at which a large quantity of heat enters and exists. For example, a rate of losing heat through a window during heating in winter is approximately 48%, and a rate of heat entering through a window during cooling in summer reaches as much as approximately 71%. Accordingly, by appropriately controlling light and heat at a window, an enormous energy saving effect can be obtained.
A dimming mechanism is developed in view of such an object, and it has a function for controlling inflow and outflow of light and heat.
There are several types of dimming elements used for such a dimming mechanism, and a gasochromic material, an electrochromic material, etc., have been studied.
In a dimming mechanism in which a gasochromic material is used as a dimming element, a thin film material in which transmittance changes by hydrogenation and dehydrogenation is deposited on a glass or a transparent sheet; and light transmittance can be switched by exposing the thin film material to a gas including hydrogen or oxygen.
For example, Patent Document 1 discloses a gasochromic dimming component including a pair of transparent substrates, the transparent substrate being arranged to face each other; a dimming part that is formed on one of or both surfaces of the pair of the transparent substrates, the surfaces facing each other, wherein an optical property of the dimming part reversibly changes by hydrogenation and dehydrogenation; a hydrogen supply unit that introduces a gas including hydrogen into a gap between the pair of the transparent substrates; and a dehydrogenation unit that removes hydrogen from the gap between the pair of the transparent substrates. Here, the pair of the transparent substrates is directly laminated through the dimming part, and the surfaces facing each other partially contact at a region at which the dimming part is formed.
According to the gasochromic dinning component disclosed in Patent Document 1, a structure is such that the transparent substrates are directly laminated through the dimming part without providing a spacer between them, so that the volume of a space between the transparent substrates is small. Consequently, an amount of hydrogen required for hydrogenating the dimming element can be reduced.